1. Field of the Invention
The present invention is applicable to, for example, the field of analyzing technique for a processing apparatus to be used for manufacturing a semiconductor device.
2. Description of the Background Art
A plurality of processing steps are executed in manufacturing steps of a semiconductor device or the like, and a plurality of processing apparatuses are employed for executing the processing steps. Therefore, to grasp and control the performance of the plurality of processing apparatuses is one of effective methods for improving the quality of a semiconductor device. For instance, foreign objects are grasped in the inside of each processing apparatus. In this way, one or more wafers are used for controlling foreign objects in each processing apparatus, commonly called as monitor wafer, which are provided only for a single processing step.
FIG. 23 is a schematic view of conventional foreign object controlling steps. One or more monitor wafers W1 to WN is/are used in processing apparatuses 11 to 1N, respectively, each performing a process on a wafer to be product (referred to as xe2x80x9cproduct waferxe2x80x9d in the present specification; not shown). These monitor wafers W1 to WN undergo predetermined processing steps in the processing apparatuses 11 to 1N, respectively, and thereafter, are subjected to a predetermined inspection, e.g., counting of the number of foreign objects, in a foreign object inspection apparatus 2.
A measured result 28 which is an inspection result of the foreign object inspection apparatus 2, e.g., the number of foreign objects counted in each of the monitor wafers W1 to WN, is written on reports 291 to 29N by an operator for each of the monitor wafers W1 to WN and stored in a file 30 at once.
However, the monitor wafers W1 to WN generally have no rot names or wafer names assigned. Neither are they provided, in general, with names nor information that can identify an apparatus where they have been processed. In some cases, information on a foreign object inspection for a monitor wafer is treated as an ad hoc number, in which there is performed neither identification of each wafer nor data collection (storage) with a processing apparatus and a wafer itself associated with each other. Hence, the measured result 28 written on each of the reports 291 to 29N is merely ad hoc information. Therefore, it is difficult to analyze data on a specific processing apparatus over a long period of time. Further, it is difficult to perform identification afterwards as to which inspection data represents data of which wafer and data of which processing apparatus taking account of information on distributions of foreign objects on a wafer map as well. Furthermore, it is impossible to make a comparison and analysis between the data and a product wafer processed in the specific processing apparatus.
According to a first aspect of the present invention, an inspection analyzing method comprises the steps of: providing one or more monitor wafers for each of a plurality of processing steps individually performed by a plurality of processing apparatuses; performing an inspection on the one or more monitor wafers to obtain an inspection result; and assigning the inspection result an identification name for identifying each of the plurality of processing apparatuses having performed the plurality of processing steps in the step (a) on the one or more monitor wafers subjected to the inspection by which the inspection result is obtained, and storing the inspection result.
According to a second aspect of the present invention, the inspection analyzing method of the first aspect further comprises the step of (d) compiling and analyzing the inspection result stored in the step (c).
According to a third aspect of the present invention, in the inspection analyzing method of the first aspect, the step (b) includes the step of (b-1) issuing an alarm when the inspection result falls outside a predetermined allowable range.
According to, a fourth aspect of the present invention, the inspection analyzing method of the third aspect further comprises the step of (e) comparing the inspection result stored in the step (c) for a processing apparatus among the plurality of processing apparatuses in which an alarm has been issued in the step (b-1) with a defect distribution of a product wafer which has undergone the plurality of processing steps executed by the plurality of processing apparatuses.
According to a fifth aspect of the present invention, the inspection analyzing method of the first or second aspect further comprises the step of (e) comparing the inspection result stored in the step (c) with a defect distribution of a product wafer which has undergone the plurality of processing steps executed by the plurality of processing apparatuses.
According to a sixth aspect of the present invention, in the inspection analyzing method of the first or second aspect, the plurality of processing apparatuses execute the same processing steps.
According to a seventh aspect of the present invention, in the inspection analyzing method of the first or second aspect, a plurality of inspection recipes are employed in the step (b) to obtain the inspection result by each of the plurality of inspection recipes.
According to an eighth aspect of the present invention, in the inspection analyzing method of the first or second aspect, the step (b) includes the steps of: (b-1) performing the inspection before and after processes of the plurality of processing steps, respectively; and (b-2) obtaining, as the inspection result, a difference in the inspection performed before and after the processes of the plurality of processing steps, respectively.
According to a ninth aspect of the present invention, in the inspection analyzing method of the eighth aspect, in the step (b-2), the inspection result is obtained as a difference between data on the inspection obtained before the processes and that obtained after the processes, considering position coordinates of the one or more monitor wafers.
According to a tenth aspect of the present invention, in the inspection analyzing method of the first or second aspect, in the step (c), the inspection result is provided with a comment indicating the condition of a processing apparatus among the plurality of processing apparatuses that corresponds to the inspection result.
According to an eleventh aspect of the present invention, an inspection analyzing method comprises the steps of: (a) performing a plurality of inspections on a wafer to be processed in a first processing step which is executed by a first processing apparatus; (b) performing an inspection on a wafer to be processed in the first processing step and a second processing step which is executed after the first processing step; and (c) comparing a plurality of inspection results obtained by the step (a) with an inspection result obtained by the step (b).
According to a twelfth aspect of the present invention, the inspection analyzing method of the eleventh aspect further comprises the step of (d) compiling and analyzing the inspection results stored in the step (c).
According to a thirteenth aspect of the present invention, in the inspection analyzing method of any one of the first to twelfth aspects, the inspection results stored in the step (c) are converted into a file that corresponds to a browser and transmitted.
According to a fourteenth aspect of the present invention, in the inspection analyzing method of any one of the first to twelfth aspects, the inspection results stored in the step (c) are converted into a file that corresponds to a browser and transmitted.
According to a fifteenth aspect of the present invention, in the inspection analyzing method of any one of the first to fourteenth aspects, the inspection results stored in the step (c) can be delivered on a network.
With the inspection analyzing method of the first, second, thirteenth and fourteenth aspects of the present invention, desired foreign objects in a desired processing apparatus is easily grasped, processed and analyzed even when a monitor wafer generally having no rot name or wafer name is used.
With the inspection analyzing method of the third aspect of the present invention, abnormality of a processing apparatus becomes known immediately after a measured result is obtained.
With the inspection analyzing method of the fourth aspect of the present invention, it is possible to know in what range a product wafer is affected by a processing apparatus where an alarm has been issued.
With the inspection analyzing method of the fifth aspect of the present invention, a processing apparatus causing a defect generated in a product wafer is easily specified.
The inspection analyzing method of the sixth aspect of the present invention makes an analysis as to whether or not an inspection result is common to processing steps executed by apparatuses of the same model which are under consideration, whether or not the apparatuses of the same model each have a specific cause of the inspection result, and the like.
With the inspection analyzing method of the seventh aspect of the present invention, inspection recipes are optimized, which further contributes to settings of specifications corresponding to the inspection recipes.
The inspection analyzing method of the tenth aspect of the present invention contributes to an analysis of the relation between the condition of a processing apparatus and a cause of occurrence of foreign objects due to the processing apparatus, e.g., occurrence of dust.
The inspection analyzing method of the eighth, ninth, eleventh and twelfth aspects of the present invention facilitates a grasp of an inspection result such as an increase in the number of foreign objects with more reliability.
According to the semiconductor device of the fifteenth aspect of the present invention, a semiconductor device manufactured effectively is obtained.
In the present invention, it is preferable to additionally provide a monitor wafer with a name that can identify a processing apparatus where the monitor wafer has been processed. This facilitates identification from which processing apparatus data comes taking account of information on distributions of foreign objects on a wafer map as well. A wafer designed specifically for monitoring may be employed as the monitor wafer according to the present invention, whereas a product wafer may be specified as a monitor wafer in the midstream of processing or may be previously specified as such. Taking a product wafer as a monitor wafer from the midstream of processing may allow saving of the labor of introducing an extra wafer, resulting in cost reduction. On the other hand, use of a wafer specifically designed for monitoring allows inspection conditions to be set more freely, so that severe management is advantageously exercised.
The present invention is directed to realize an analysis of inspection results obtained over a long period of time cannot be made sufficiently with conventional management using the file 30.